AJ567

Great idea!

Yes that's possible, but you would need a USB Midi host to convert the 5-pin midi output from the HX to USB-midi format (which is what the C4 accepts.) The only commercially available device that does this is the Disaster Area Midi Ghost (as far as I know). However, if you are comfortable with DIY, you can make your own USB host. I did this very recently and it worked a treat. See my post here: You could also put a Source Audio Neuro Hub between the HX and C4, but it's kind of overkill if you just need to change presets on the one pedal.

The current doubler is just a 2 way daisy chain, used 'backwards'. So yes you can also use it the other way round as you propose (which is the same thing as a 2 way daisy chain used in the normal way).

Building on an earlier post... I added a little board to my expression pedal with a couple of trimmers, which allows control over the shape of the sweep. Well pleased with how well this worked! I made an excel model to demonstrate what effect different resistor values have on the curve. Feel free to have a play: Pot network.xlsx

Built a USB Midi host based on a design I found here. Works a treat! Nice alternative to the Disaster Area Midi Ghost. It's my first proper attempt at this kind of thing so I'm pretty chuffed.

I think the source audio eq2 can do this

If you're comfortable soldering you might be able to add resistors to the pedal to make the sweep closer to what you want. See here:

I've been messing around with adding resistors to my expression pedals to change the shape of the sweep. You can get some pretty cool results doing this. I made an excel model to show what different resistor values do in different positions. Thought I'd post it here in case it's useful to somebody. Feel free to hit me with any Qs. pot network.xlsx

Bought an expression pedal from Peter, he is a gent to deal with. Thanks a bunch!

Under 70 quid including vat, even with Brexit-related fees and faff it'll end up being like 60% off RRP. https://www.thomann.de/gb/ebs_retracer_delay_workstation.htm It's some kind of close-out deal apparently, it says out of stock but you can order it at that price then receive a few weeks later. Looks like a cool pedal, I'm surprised it didn't really take off and now EBS are canning it, it seems. Currently trying to convince myself I don't need yet another delay...

Could be a shielding/grounding issue in the pedal itself, or on one of your cables. You can test for poor shielding on the pedal by wrapping in tin foil - you need to make sure that the tin foil has a good connection to the sleeve of the jacks on both of your cables. If the problem goes away, you have your answer.

The Spectrum is pretty to easy to adjust on the fly. Four most important parameters are adjusted via the 4 knobs on the front, just like a standard pedal. You can push the 'alt' button and access another four parameters via the same knobs. The app is easy to use, as is the desktop version. I prefer the desktop mainly because it's nicer to have a bigger screen and more the presentation of what you are tweaking (i.e. the options and knobs etc.) is more detailed. The infrastructure Source Audio have built with the whole neuro app system is impressive. Easy to load presets and there's a busy community of people making new sounds; everything is stored in the cloud so you can access it from whichever device and nothing gets lost. Oh and the pedal/software is amazing. You can create pretty much any filter sound you can imagine. There are envelope phaser sounds available but I don't know the Pigtronix enough to comment specifically. Basically... get one, you won't regret it. I certainly won't be buying any more filter pedals for a very long time!

Great comparison! IMO they're sufficiently similar that the choice is really about how much you value the other features/tones available on that particular pedal.

Buzz in the high positions only usually means too much relief, so you need to tighten the truss a little. I have one of these status necks and the truss adjustment works just as you would expect on a wooden neck. I like to follow the 'even buzz' method when setting up mine. Set the saddles so that you have correct radius, then lower them all evenly until you have some strong buzz (in the high positions, in your case). Then straighten the truss until you have the same amount of buzz up and down the neck. That's when you know the relief is about right. Then raise saddles up until you have the action you like (and no buzz).